the game on two difficulty settings with a few fully upgraded weapons and ninpos. On March 2, 2004, a year later than originally planned, Tecmo released Ninja Gaiden in the United States. Regional censorship As released, Ninja Gaiden contained bloody acts of violence, decapitations and grotesque monsters. The North American games rating body, the Entertainment Software Rating Board (ESRB), rated it as a "Mature" game, which prohibits sale to anyone under the age of 17 in several states. The depiction of beheadings, though, attracts stricter ratings in other parts of the world. In Germany, the Unterhaltungssoftware Selbstkontrolle (USK) deemed these excessive, and refused to rate the game at all. Since this had the potential to place Ninja Gaiden in Germany's "List of Media Harmful to Young People", which would have meant that shops could neither advertise the game nor sell it unless by request to customers of 18 years or older, Tecmo censored the European PAL version to obtain a USK rating. A year later, Tecmo managed to obtain a USK 18+ rating for the uncensored release of Ninja Gaiden Black. Japan's Computer Entertainment Rating Organization (CERO) rated Ninja Gaiden and Black, on their release, as 18+ games. At the time, CERO ratings acted as guidelines for consumers. However, on March 1, 2006, the Japanese rating system changed. A scale from A to D was introduced, with an additional Z rating for games with large amounts of gore, violence and crime. The Z rating is legally enforced, it being illegal to sell such games to anyone under the age of 18. As a result, Tecmo removed the human beheadings in Sigma to obtain a D rating for the East Asian market. However, CERO reclassified the two previous games as D, despite them also depicting human decapitations. Post-release Team Ninja kept working on the Ninja Gaiden project after its release, with the aim of pushing the action genre and their first such game as far as they could. To this end, they released downloadable expansions, known as Hurricane Packs, free of charge. Itagaki said that since the packs were born out of his team's interest, they did not care to charge players for their efforts. The two packs were available over Xbox Live in the third quarter of 2004. Hurricane Pack 1 was a revamped version of Story Mode; Team Ninja tweaked the encounters and artificial intelligence (AI) of Ryu's foes